1. Field of the Invention
This invention relates to a fluid pressure device applicable to an oil hydraulic system and also to a hydraulic system, and more particularly, to a pulsation damping or absorbing means or device for preventing fluid hammering or pulsation from occurring in a fluid pressure device and can also be used to transfer such fluid.
2. Prior Art
As a kind of this apparatus, there is one which comprises, a cylindrical pressure vessel, an inlet and an outlet, a cylindrical resilient diaphragm and an inner cylinder within said pressure vessel, both of which are disposed concentrical with each other. The inner cylinder is formed with a plurality of communicating holes on its outer surface in order to provide for passage through the cylinder wall of fluid under pressure. One or more resilient valve shoes of arcuated shape, namely arched leaf spring are located, each being coupled to the inner cylinder by pins to cover the communicating holes so as to prevent the resilient diaphragm member from being damaged when it is pushed into the communicating holes. (See Japanese Patent No. 646410 and U.S. Pat. No. 3,483,892). It is necessary for this arched leaf springs to be fabricated with such a thickness enough to have a strength that the leaf spring do not enter into the communicating holes when they are urged by the diaphragm toward the communicating holes, so that the arched leaf springs do not damage the resilient diaphragm.
If the thickness of the spring is made excessively large, however, the arched leaf spring would become difficult to be deformed, then they are not able to tightly contact the arched contour of the inner cylinder to completely close the communicating holes even when they are urged by the resilient diaphragm, thereby the resilient diaphragm member will enter into the gap formed between the inner cylinder and the leaf spring. Thus it becomes necessary to select the thickness of the arched leaf spring enough to satisfy the above requirement, however, such a leaf spring 1, under the flow of fluid in a direction as shown by arrow mark A3 shown in FIG. 18, would be caused to jump upward at their two opposite transverse side edges 1a and 1b by the force of the fluid, while being held by the pin 4. Consequently, there arises a concentration of fluid force on the leaf spring 1 caused by the flow of the fluid around the vicinity of the pin 4, which would result in damage of the leaf spring at that portion.